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The folding patterns and deployment dynamic characteristics of conical inflatable capsule structures were investigated. A six-fold-line method of packing a conical shell surface was designed. The fold-line layouts and relation formulas of the fold angles were determined. The folded state of the inflatable capsule structure was parametrically modeled; then, the deployment dynamic analysis model was established using ANSYS/LS-DYNA software. The dynamic characteristics of the inflatable capsule structure in orbit were numerically simulated. Thus, the deployment configurations and the time history curves of the dynamic characteristics were obtained. The results verified the feasibility of the fold pattern and the deployment dynamic analysis model. The influences of the residual gases from the packing process on the subsequent deployment process were investigated. The results indicated that a small amount of residual gas can lead to structures that cannot deploy smoothly, and two methods were presented to avoid this challenge. These works provide technical support for the structural designs of this type of inflatable capsule structure.

The high concentration of ammonium chloride in the wastewater from the precipitation of rare earth carbonate was studied by an electrolytic method in this paper. The decomposition rate of ammonium chloride is obtained by electrolysis experiment, and the main components of wastewater can be transformed into raw and auxiliary materials that can be reused in the rare earth smelting process, so as to achieve the purpose of treating rare earth carbonate precipitation wastewater and provide a new method for the treatment of rare earth carbonate precipitation wastewater. The principle of the electrolysis process is analyzed in this study, and the optimum electrolysis factor is determined by the condition experiment. The changes in membrane materials and electrode materials before and after use are discussed. The experiments of stripping ammonia water and the reaction conditions of the formation experiment of ammonium bicarbonate are studied. The rare earth carbonate precipitation wastewater with the initial ammonium chloride concentration of 50 g/L was electrolyzed. The concentration of ammonia chloride was reduced to 3.5 g/L after electrolysis, and the electrolysis rate exceeded 90%. The purity of the ammonium chloride after electrolysis could exceed 93%. No industrial reagent was introduced in the electrolysis process, and no other pollutants were produced. [ABSTRACT FROM AUTHOR]

A precious metal catalyst with loaded Pt single atoms was prepared and used for the complete oxidation of C 3 H 6 O. Detailed results show that the T 100 of the 1.5Pt SA/γ-Al 2 O 3 catalyst in the oxidation process of acetone is 250 °C, the TOF of Pt is 1.09 × 10 -2 s -1 , and the catalyst exhibits good stability. Characterization reveals that the high dispersion of Pt single atoms and strong interaction with the carrier improve the redox properties of the catalyst, enhancing the adsorption and dissociation capability of gaseous oxygen. DFT calculations show that after the introduction of Pt, the oxygen vacancy formation energy on the catalyst surface is reduced to 1.2 eV, and PDOS calculations prove that electrons on Pt atoms can be quickly transferred to O atoms, increasing the number of electrons on the σ p * bond and promoting the escape of lattice oxygen. In addition, in situ DRIFTS and adsorption experiments indicate that the C 3 H 6 O oxidation process follows the Mars-van Krevelen reaction mechanism, and CH 2 =C(CH 3 )=O (ads) , O* (O 2 - ), formate, acetate, and carbonate are considered as the main intermediate species and/or transients in the reaction process. Particularly, the activation rate of O 2 and the cleavage of the -C-C- bond are the main rate-determining steps in the oxidation of C 3 H 6 O. This work will further enhance the study of the oxidation mechanism of oxygenated volatile organic pollutants over loaded noble metal catalysts., Competing Interests: Declaration of Competing Interest Hereby declare that the authors have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Influence of dust catchers on PM10 emission characteristics was determined experimentally at the inlet and outlet of dust catchers at five different power plants. Electrical low pressure impactor (ELPI) with a sampling system, which consisted of an isokinetic sampler probe, pre-cut cyclone, two-stage dilution system and sample line to the instruments, were used to measure in situ. Size distribution is measured on the range from 0.03 microm to 10 microm in aerodynamic diameter. The results show that the testing system can be used widely for sampling of particulate matters from stationary sources. Before and after all the dust catchers, the particle number size distributions display the bimodal distribution which contained the submicron mode and the coarse mode with a peak around 0.07-0.12 microm and 0.76-1.23 microm, respectively. The minimum collection efficiency of the ESP and the bag-house both appear in the particle size range of 0.1-1 microm. In this size range, bag-house collection efficiency is higher than that of ESP. The ESP collection efficiencies of PM1 and PM2.5 based on the number concentration are also lower than that of PM10. The mass concentration of PM10 is mainly dominated by the particles which are larger than 1 microm, while the number concentration is dominated by the particles which are smaller than 0.1 microm. Mass and number size distributions measured after ESP can be seen that mass and number concentration of PM10 will increase obviously by rapping the last electric field. Furthermore, the ESP collection efficiencies based on the number concentration and mass concentration were both decreased by ESP rapping with different degree; and the maximum drop degree was appeared in PM1.

Life Cycle Assessment (LCA) was used to compare energy consumption and pollutant emissions of two oxygen biofuels, ethanol and methyl ester, which were mixed with gasoline and diesel oil at levels of 10% and 30% of the biofuel. The future of oxygen-containing biofuels was analyzed and forecasted. The results show that the mixture of biofuels and petroleum products can reduce crude oil consumption, but only methyl ester alternative fuel can reduce fossil fuel consumption. Use of methyl ester mixtures would reduce NOx by 50% compared to gasoline or diesel on a life cycle basis; however, NOx would increase using ethanol. Each alternative fuel mixture reduced PM10 emissions from the vehicle and methyl ester decreased VOCs. The SO2 emissions from the fuel production processes, which account for about 80% of SO2 life cycle emissions, must be strictly controlled.

Ammonia plant tail gas is an important CO source for C1 chemistry if an efficient separation/purification technology is available. Presented is pressure swing adsorption using a home made catalyst PU1 for recovery of CO from ammonia plant tail gas. A performance comparison of PU1 with a commercial zeolite was also presented. The pilot plant experiments were carried out in an intermission one-bed PSA unit with ammonia plant tail gas and a feed flow rate of 0.2-0.8 m3/h. The purity and recovery of CO was studied under various operating conditions. The operating conditions for the process were optimized and an optimum cyclic sequence of operation steps was proposed. A good performance of PU1 in the process was experimentally demonstrated. Product gas with a CO purity over 98% could be produced at a CO recovery of 75% for a feed gas CO concentration of 30% and gas pressure of 0.3 MPa.